5
Standards and guidelines for repairing concrete structures
M. Raupach, Institute of Building Materials Research of Aachen University, Germany; and L. Wolff, Consulting Engineers, Raupach Bruns Wolff GmbH & Co. KG, Germany
Abstract: This chapter deals with international regulations for condition evaluation, repair and maintenance of concrete structures and is based largely on the new European series of standards EN 1504. First of all the systematics of concrete repair is explained as defined in EN 1504. It consists of the assessment of the structure, followed by the selection of options, principles and methods for protection and repair and finally maintenance of the structure. According to this order, selected relevant international regulations are listed for the following subjects: condition assessment, surface preparation, concrete restoration, strengthening, surface protection, crack injection, corrosion protection and maintenance. We have tried to list all relevant regulations, but of course it is not possible to find all of them. Consequently, the list of regulations cannot be complete. It was also not intended to give comments to the contents of all these regulations, but to have a structured overview on the international regulations. Key words: concrete restoration, EN 1504 standard, concrete structure condition assessment, crack injection surface protection, surface preparation, corrosion protection, maintenance.
5.1
Introduction
This chapter presents worldwide legislation, standards, guidelines and recommendations for diagnosis and repair of concrete structures. The structure of the European standard EN 1504 is presented in detail as this standard covers all phases of a repair project, including diagnosis, selection of repair method, choice of repair material and maintenance. However, other relevant standards and regulations are also listed.
5.2
Systematics of concrete repair according to EN 1504
5.2.1 General With the EN 1504 a new European standard on protection and repair of concrete structures has been worked out, based on the actual state of knowledge regarding the properties of the products, the principles for the 141
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Failure, distress and repair of concrete structures
use of the products, application and quality control. It consists of 10 main standards and 61 standards for test methods. As shown in Fig. 5.1, parts 2 to 7 regulate the performance of the products and systems for protection and repair of concrete structures with respect to CE marking (Conformité Européenne). The use of the products is based on a logical sequence consisting of options (repair strategies), repair principles and repair methods, which are listed in tables in part 9 of EN 1504. This scheme ensures that suitable products are selected based on the requirements of the practical case. At the end of 2008 this new series of standards replaced the existing national standards in Europe. This will also have significant impact for other countries. Part 1 gives definitions, part 8 regulates the quality control of the products and part 10 gives a general guideline for site application and quality control of the works. To allow CE marking of the products, 61 standards describing test methods for the different properties of the products have been prepared. These standards ensure that testing of the products will be according to the same standards for all products for protection and repair of concrete structures used in Europe.
5.2.2 Phases of repair projects The phases of repair projects follow a logical sequence, which is dominated by engineering aspects. Figure 5.2 gives a general scheme according to figure A1 within annex A of EN 1504-9. This figure shows the well-known elements of assessment, planning, design and quality control. However, the
EN 1504-1 Definitions
EN 1504-9 Principles for the use of the productds
EN 1504-2 to 7: Products – surface protection – repair mortars
EN 1504-10 Site application and quality control of the works
– bonding materials – injection materials – anchoring products – coatings for steel
Further test methods
Test methods (61 standards) EN 13 396 (chloride ingress) · · · · EN 14 497 (filtration stability)
EN 1504-8 Quality control of the products
5.1 Structure of EN 1504.
Project phases Process of assessment
Management strategy
Design of repair work
Repair work
Acceptance of repair work
Basic considerations and actions ∑ Condition and history of structure
∑ Defects and their classification and causes
∑ Options
∑ Documentation
∑ Safety/structural appralsal during protection and repair
∑ Methods
∑ Previous repair and maintenance
∑ Principles
∑ Safety/structural appraisal before protection and repair
∑ Intended use of products ∑ Requirements – substrate – products – work
∑ Choice and use of products and systems and methods and equipment to be used
∑ Specifications
∑ Tests of quality control
∑ Drawings
∑ Health and safety
∑ Acceptance of testing ∑ Remedial works ∑ Documentation
∑ Safety/structural appraisal after protection and repair
Relevant clauses in EN-1504-9 and other parts of the EN 1504 series ∑ Clause 4 of this European Standard
∑ Clause 4 of this European Standard
∑ Clauses 5 and 6 of this European Standard
∑ Clauses 6, 7, 9 and 10 of this European Standard ∑ EN 1504-10
∑ Clause 8 of this European Standard ∑ EN 1504-10
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5.2 The phases of repair projects according to EN 1504-9.
∑ EN 1504-2 to EN 1504.7 ∑ Clauses 6, 7 and 9 of this European Standard
Standards and guidelines for repairing concrete structures
Information about the structure
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systematics of general planning is quite innovative. It consists of a hierarchy of levels, namely options, principles and methods, which are described in more detail in Section 5.2.4.
5.2.3 Process of assessment A broad and detailed assessment is essential for the success of a repair project. The purpose of the main assessment is shown in Fig. 5.3. With respect to later planning of repair, generally a distinction should be made between defects in concrete and defects caused by reinforcement corrosion. Common causes of defects according to figure 1 of EN 1504-9 are shown in Fig. 5.4. More details on requirements for assessment are given in EN 1504-9.
5.2.4 Options, principles and methods for protection and repair As already mentioned, the rules for the use of products and systems for protection and repair of concrete structures are based on a hierarchy of different levels, namely options, principles and methods. According to EN 1504-9 the options shown in Fig. 5.5 shall be taken into account in deciding the appropriate action to meet the future requirements for the life of the structures: For protection and repair, different principles have been defined, separately for repair and prevention of damages to the concrete and damages induced by reinforcement corrosion. Table 5.1 shows the six principles for protection and repair of concrete and the five principles to prevent damages due to rein forcement corrosion, respectively. These principles are based on the RILEM Technical Recommendation 124-SRC ‘recommendation for repair strategies for concrete structures damaged by reinforcement corrosion’. To protect or repair a concrete structure according to the principles, different methods are available. Figures 5.6–5.9 of this chapter give some examples and short
Purposes of main assessment
Identification of the causes of defects
Establishment of extent of defects
Establishment of prospective defects
Assessment of the effect of defects on structural safety
Identification of locations with need for repair
5.3 Purposes of main assessment according to EN 1504-9.
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145
Common causes of deterioration
Concrete
Mechanical
Chemical
Physical
∑ Abrasion ∑ Fatigue ∑ Impact ∑ Overload ∑ Movement (e.g. settlement) ∑ Explosion ∑ Vibration ∑ Alkali–Aggregate reaction ∑ Aggressive agents (e.g. sulfates, salts, soft water) ∑ Biological action ∑ Freeze/thaw ∑ Thermal effects ∑ Salt crystallization ∑ Shrinkage ∑ Erosion ∑ Wear
Reinforcement corrosion
Carbonation
∑ Cement content and type ∑ w/c ratio ∑ Curing ∑ Rainfall ∑ Temperature/humidity
Corrosive contaminants
∑ At mixing: – Chloride salts ∑ From external environment – Sea water – Road salt – Other contaminants
Stray currents
Fire
5.4 Common causes of defects according to EN 1504-9.
descriptions of selected principles and methods of EN 1504-9. Altogether, 43 methods are described within EN 1504-9. Not all of them are covered by the EN 1504 series, but some are covered by other standards, and some of them are actually not standardised, but expected to be regulated in the future. The system of options, principles and methods is the basis for the selection of products by the designer. The process of planning and selection of products is described in the next section. Figures 5.6–5.9 give examples of certain cases, with the performance charac teristics relevant for the selected repair methods. EN 1504-2–7 contain the performance characteristics of the products together with the corresponding test methods. In this way, the products are selected individually for the demands of the special case of repair or protection of a concrete structure. As a result, the products are described by a list of required performance characteristics instead of simple classes, resulting in a high level of flexibility. Finally inspection and maintenance requirements shall be defined by the designer.
5.2.5 Planning and selection of products Figure 5.10 shows the systematics of planning according to EN 1504-9. As already shown in Fig. 5.2, the planning starts with the assessment of the status of the structure. The next steps are selection of options (repair
146
Prevention or reduction of further deterioration, without improvement of the concrete structure
Improvement, strengthening or refurbishment of all or parts of the concrete structrure
Reconstruction of part or all of the concrete structure
Demolition of all or part of the concrete structure
5.5 Options for deciding the appropriate action to meet the future requirements for the life of the structures according to EN 1504-9.
Failure, distress and repair of concrete structures
Do nothing for a certain time but monitor
Re-analysis of structural capacity, possibly leading to downgrading of the function of the concrete structure
Standards and guidelines for repairing concrete structures
147
Table 5.1 Principles for repair and protection for damages of the concrete according to EN 1504-9 Principle Examples of methods based on the principles Principles and methods related to defects in concrete 1. Protection against 1.1 Hydrophobic impregnation ingress 1.2 Impregnation 1.3 Coating 1.4 Surface bandaging of cracks 1.5 Filling of cracks 1.6 Transferring cracks into joints 1.7 Erecting external panelsa 1.8 Applying membranesa 2. Moisture control
2.1 2.2 2.3 2.4 2.5
Hydrophobic impregnation Impregnation Coating Erecting external panels Electrochemical treatment
3. Concrete restoration 3.1 Hand-applied mortar 3.2 Recasting with concrete or mortar 3.3 Spraying concrete or mortar 3.4 Replacing elements
Relevant Part of EN 1504 (where applicable) 2 2 2 5
2 2 2
3 3 3
4. Structural strengthening
4.1 Adding or replacing embedded or external reinforcing bars 4.2 Adding reinforcement anchored in pre-formed or drilled holes 4.3 Bonding plate reinforcement 4.4 Adding mortar or concrete 4.5 Injecting cracks, voids or interstices 4.6 Filling cracks, voids or interstices 4.7 Prestressing – (post-tensioning)
6 4 3,4 5
5. Increasing physical resistance
5.1 Coating 5.2 Impregnation 5.3 Adding mortar or concrete
2 2 3
6. Resistance to chemicals
6.1 Coating 6.2 Impregnation 6.3 Adding mortar or concrete
2 2 3
rinciples and methods related to reinforcement corrosion P 7. Preserving or 7.1 Increasing cover with additional restoring passivity mortar or concrete 7.2 Replacing contaminated or carbonated concrete 7.3 Electrochemical realkalisation of carbonated concrete 7.4 Realkalisation of carbonated concrete by diffusion 7.5 Electrochemical chloride extraction
5
3 3
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Failure, distress and repair of concrete structures
Table 5.1 Cont’d Principle Examples of methods based on the principles
Relevant Part of EN 1504 (where applicable)
8. Increasing resistivity 8.1 Hydrophobic impregnation 8.2 Impregnation 8.3 Coating
2 2 2
9. Cathodic control
9.1 Limiting oxygen content (at the cathode) by saturation or surface coating
10. Cathodic protection
10.1 Applying an electrical potential
1. Control of anodic 1 areas
11.1 Active coating of the reinforcement 7 11.2 Barrier coating of the reinforcement 7 11.3 Applying corrosion inhibitors in or to the concrete
a
These methods may also be applicable to other principles.
Principle no.
Principle and its definition
Principle 1 [PI] ‘Protection against ingress’ Reducing or preventing the ingress of adverse agents, e.g. water, other liquids, vapour, gas, chemicals and biological agents.
Methods basd on the principle 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8
Hydrophobic impregnation Impregnation Coating Surface bandaging of cracks Filling of cracks Transferring cracks into joints Erecting external panels Applying membranes
Principle no.
Principle and its definition
Methods basd on the principle
Principle 2 [MC]
Moisture control Adjusting and maintaining the moisture content in the concrete within a specified range of values.
2.1 2.2 2.3 2.4 2.5
Hydrophobic impregnation Impregnation Coating Erecting external panels Electrochemical treatment
5.6 Examples for surface coating according to methods 1.3 and 2.3 of EN 1504-9.
Standards and guidelines for repairing concrete structures
Principle no. Principle 3 [CR]
Principle and its definition
149
Methods based on the principle
Concrete restoration
3.1 Applying mortar by hand Restoring the original concrete 3.2 Recasting with concrete of an element of the structure 3.3 Spraying concrete or mortar to the originally specified shape 3.4 Replacing elements and function Restoring the concrete structure by replacing part of it.
5.7 Example of the preparation of a concrete surface for applying mortar by hand according to method 3.1 of EN 1504-9.
strategy), repair principles and repair method, as defined in the previous section. Based on this selection scheme, the repair materials can be chosen. EN 1504-9 defines performance characteristics for every repair method, separately for all intended uses and for certain intended uses. The designer selects the performance characteristics based on the requirements of the special repair project and the selected repair methods.
5.3
International regulations for condition evaluation, repair and maintenance
5.3.1 General In the following sections international regulations for the different phases of a repair work are summarised. The main focus is on regulations and
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Failure, distress and repair of concrete structures
5.8 Example for recasting with concrete according to method 3.2 of EN 1504-9.
standards in the English language. An overview of the different topics in this section is given in Fig. 5.11. Additional relevant international standards are summarised in Appendix A. In these sections mainly American standards as well as European standards for testing certain properties of hardened repair products are listed.
5.3.2 Condition assessment The condition evaluation is the first highly important step in repair of all kinds of structures. The purpose of the condition evaluation is to identify and define causes and distribution of distress. In Table 5.2 different international regulations and guidelines are given, which can help to plan and carry out a condition evaluation. Nevertheless, these publications can only be a helping tool as the condition evaluation has to take into account all factors relating to the structure, which can of course not be part of a general recommendation.
5.3.3 Surface preparation A careful and intensive surface preparation of both the steel and the concrete is the basis for a successful repair not only for concrete restoration or the
Standards and guidelines for repairing concrete structures
Principle no.
Principle and its definition
Principle 4 [SS] Structural strengthening
151
Methods based on the principle 4.1 Adding or replacing embedded or external reinforcing bars
Increasing or restoring the structural load bearing 4.2 Adding reinforcement anchored in capacity of an element pre-formed or drilled holse of the concrete structure. 4.3 Bonding plate reinforcement 4.4 Adding mortar or concrete 4.5 Injecting cracks, voids or interstices 4.6 Filling cracks, voids or interstices 4.7 Prestressing – (post-tensioning)
5.9 Example for injection of cracks according to method 4.5 of EN 1504-9.
application of surface protection systems, but also for crack injection, strengthening or corrosion protection. Table 5.3 gives an overview.
5.3.4 Concrete restoration Concrete restoration is one basic part of all repair projects of reinforced concrete structures. It covers materials for repair, preparation, application methods and contractual issues. In Tables 5.4–5.8 important international regulations for concrete restoration, especially the areas of materials, shotcrete, application of mortars as well as contractual issues are summarised.
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Failure, distress and repair of concrete structures Assessment of the status of the structure (defects …)
Elaboration of the repair strategy (do nothing, repair, …, demolition)
Definition of the repair principles (e.g. protection against ingress …)
Selection of the repair method (e.g. impregnation …)
Definition of the repair materials (strength, modulus, adhesion, etc.)
Definition of inspection and maintenance requirements
5.10 Systematic of planning according to EN1504–9.
Condition assessment (see Section 5.3.2) Surface preparation (see Section 5.3.3) Concrete restoration (see Section 5.3.4)
Strengthening (see Section 5.3.5)
Surface protection (see Section 5.3.6)
Crack injection (see Section 5.3.7)
Corrosion protection (see Section 5.3.8)
∑ Materials ∑ Surface preparation ∑ Application methods Maintenance (see Section 5.3.9)
5.11 Overview of the different topics of regulations within the following sections.
5.3.5 Strengthening For strengthening, nowadays externally bonded fibre-reinforced polymer (FRP) systems or the application of shotcrete are mainly used. The topic of shotcrete is part of Section 5.3.4, therefore Table 5.9 mainly focuses on the application of externally bonded FRP systems to reinforced concrete elements.
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153
Table 5.2 Overview of international guidelines and recommendations for condition evaluation Notification Name
Date of Country issue
ACI 201.1R-92
Guide for making a Condition Survey of Concrete in Service
1997
USA
ACI 224.1R-93
Causes, Evaluation and Repair of Cracks in Concrete Structures
1998
USA
ACI 228.2R-98
Non-destructive Test Methods for Evaluation of Concrete in Structures
1998
USA
ACI 364.1R-07
Guide for Evaluation of Concrete Structures before Rehabilitation
2007
USA
ACI 437R-03
Strength Evaluation of Existing Concrete Buildings
2003
USA
ICRI Guideline No. 03736
Guide for the Evaluation of unbonded Post-Tensioned Concrete Structures
2005
USA
CS-ES-1.1
System for Rapid Assessment of Quality of Concrete in Existing Structures
1985
USA
CS-ES-1.7
Petrographic Examination of Distress in Concrete
undated USA
CS-ES-1.13
Site Inspection and Sampling Concrete 1996 Damaged by Alkali–Silica Reaction
USA
AIJ
Recommendation for practice of survey, diagnosis and repair for deterioration of reinforced concrete structures
1997
Japan
RILEM Report 36 TC 184-IFE
Industrial Floors, State-of-the-Art Report Evaluation and Quality Assessment
2006
RILEM
RILEM TC-154-EMC Recommendations of: “Electrochemical 2004 techniques for measuring metallic corrosion.” Test methods for on-site corrosion rate measurement of steel reinforcement in concrete by means of the polarisation resistance method
RILEM
RILEM TC 43-CND
Draft recommendation for in situ concrete strength determination by combined non-destructive methods
1993
RILEM
CEB Bulletin 243
Strategies for Testing and Assessment of Concrete Structures affected by Reinforcement Corrosion
1998
Switzerland
BRE Digest 434
Corrosion of Reinforcement in Concrete: Electrochemical Monitoring
1998
UK
BRE Digest 444
Corrosion of Steel in Concrete Part 1: Durability of Reinforced Concrete Structures Part 2: Investigation and Assessment
2000
UK
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Failure, distress and repair of concrete structures
Table 5.3 Overview of international guidelines for repair materials in the field of surface preparation Notification Name
Date of Country issue
ICRI Guideline No. 03730
Guide for Surface Preparation for the Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion
1995
USA
CS-MR-1.14
Concrete Removal Techniques: Selection
1994
USA
CS-MR-2.1
Concrete Surface Preparation Prior to Repair
undated USA
Table 5.4 Overview of international guidelines for materials for repair in the field of concrete restoration Notification Name
Date of Country issue
ACI 530R-93
Use Epoxy Compounds with Concrete
1998
USA
ACI 530.5R-92
Guide for the selection of Polymer
1997
USA
ACI 546.1R-80
Guide for Repair of Concrete Bridge Superstructures
1980
USA
ACI 546.3R-06
Guide for the Selection of Materials for 2006 the Repair of Concrete
USA
ICRI Guideline No. 03733
Guide for Selecting and Specifying Materials for Repair of Concrete Surfaces
USA
1996
Table 5.5 Overview of international guidelines for the use of shotcrete in the field of concrete restoration Notification Name
Date of Country issue
ACI 506.2-95
Specification for Shotcrete
1995
USA
SCA-UK
An Introduction to Sprayed Concrete
1999
UK
ACI 506.4R-94
Guide for the Evaluation of Shotcrete
1994
USA
ACI 506R-90
Guide to Shotcrete
1995
USA
5.3.6 Surface protection An overview on international regulations for surface protection of concrete parts is given in Table 5.10.
Standards and guidelines for repairing concrete structures
155
Table 5.6 Overview of international guidelines for application of mortars in the field of concrete restoration Notification Name
Date of Country issue
ACI 503.4-92
Standard Specification for Repairing Concrete with Epoxy Mortars
1997
USA
ACPA TB-020.02P
The Concrete Pavement Restoration Guide: Procedures for Preserving Concrete Pavements
1998
USA
ACPA TB-002.02P
Concrete Paving Technology – Guidelines for Full Depth Repair
1995
USA
ACPA TB-003.02P
Concrete Paving Technology – Guidelines for Partial Depth Spall Repair
1998
USA
ACPA TB-005P
Technical Bulletin – Guidelines for Unbonded Concrete Overlays
1990
USA
ACPA TB-008.01P
Diamond Grinding and Concrete Pavement Restoration
2000
USA
ACPA TB-007P
Technical Bulletin – Guidelines for Concrete Bonded Overlays
1990
USA
Table 5.7 Overview of international guidelines for application methods in the field of concrete restoration Notification Name
Date of Country issue
ICRI Guideline No 03731
Guide for Selecting Application Methods for the Repair of Concrete Surfaces
1996
USA
ACPA TB-007P
Technical Bulletin – Guidelines for Concrete Bonded Overlays
1990
USA
Table 5.8 Overview of international guidelines for contractual issues in the field of concrete restoration Notification Name
Date of Country issue
CRA
Standard Method of Measurement for Concrete Repair
1997
UK
CS TR 38
Patch Repair of Reinforced Concrete Subject to Reinforcement Corrosion
1991
USA
ICRI Guideline No. 03735
Guide for Methods of Measurement and Contract Types for Concrete Repair Work
2000
USA
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Failure, distress and repair of concrete structures
Table 5.9 Overview of international guidelines for strengthening Notification Name
Date of Country issue
ACPA TB-018P
Concrete Paving Technology–Slab Stabilization Guidelines for Concrete Pavements
1994
USA
ACI 440.2R-02
Guide for the Design and Construction 2002 of Externally Bonded FRP Systems for Strengthening concrete Structures
USA
CNR-DT-200
Guide for the Design and Construction 2004 of Externally Bonded FRP Systems for Strengthening Existing Structures – Materials, RC and PC structures, masonry structures
Italy
fib bulletin 35
Retrofitting of concrete structures by externally bonded FRPS, with emphasis on seismic applications
2006
Switzerland
fib bulletin 40
FRP reinforcement in RC structures
2007
Switzerland
Table 5.10 Overview of international guidelines for surface protection Notification Name
Date of Country issue
CS TR 50
Guide to Surface Treatments for Protection and Enhancement of Concrete
1997
UK
ICRI Guideline No. 03732
Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings and Polymer Overlays
1997
USA
AASHTO
Guide Specifications for Polymer Concrete Bridge Deck Overlays
1995
USA
5.3.7 Crack injection The purpose of a crack injection can be to strengthen the structure, either by providing a barrier against aggressive agents or by ensuring the functionality by sealing existing cracks. In order to ensure a successful and durable crack injection, both the cause of the crack and the annual change of the crack width have to be taken into account when choosing an appropriate crack grout. Helpful international regulations for crack injection of concrete parts are listed in Table 5.11.
5.3.8 Corrosion protection of the reinforcement Concrete normally provides the steel reinforcement with an alkaline corrosion protection. Nevertheless, ingress of chlorides or carbonation may lead to
Standards and guidelines for repairing concrete structures
157
Table 5.11 Overview of international guidelines for crack injection Notification Name
Date of Country issue
ACI 224.1R-93
Causes, Evaluation and Repair of Cracks in Concrete Structures
1998
USA
ICRI Guideline
Guide for Verifying Field Performance of Epoxy Injection of Concrete Cracks
1998
USA
ACI 504R-90
Guide to Sealing Joints in Concrete Structures
1997
USA
ACPA TB-012P
Concrete Paving Technology–Joint and 1995 Crack Sealing and Repair for Concrete Pavements
USA
CS-MR-3.1
Selection of a Crack Repair Method
1985
USA
CS-MR-3.2
Crack Repair Method: Routing and Sealing
1985
USA
CS-MR-3.3
Crack Repair Method: Drilling and Plugging
1985
USA
CS-MR-3.4
Crack Repair Method: External Stressing 1985
USA
CS-MR-3.5
Crack Repair Method: Stitching
1985
USA
CS-MR-3.6
Crack Repair Method: Conventional Reinforcement
1985
USA
CS-MR-3.7
Crack Repair Method: Grouting (Portland-Cement and Chemical)
1985
USA
CS-MR-3.8
Crack Repair Method: Drypacking
1991
USA
CS-MR-3.9
Crack Repair Method: Epoxy Injection
1985
USA
CS-MR-3.10
Crack Repair Method: Flexible Sealing or Mastic Filling
undated USA
CS-MR-3.11
Crack Repair Method: Polymer Impregnation
1991
CS-MR-3.12
Hydrostatic Tests of Injection Ports Used for In Situ Repair of Concrete
undated USA
USA
initiation of reinforcement corrosion. Based on the cause of reinforcement corrosion, existence of chlorides or carbonation of the surrounding concrete, different electrochemical, physical or chemical principles exist to stop the corrosion process and to repair corrosion damaged concrete parts. The regulations listed in Table 5.12 may help to understand the typical processes of reinforcement corrosion as well as acting as a guide for selection of suited corrosion protection or repair methods for reinforced concrete parts.
5.3.9 Maintenance Maintenance is important for new as well as for repaired structures to ensure the functionality over the whole life-cycle. Continuous maintenance helps
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Failure, distress and repair of concrete structures
Table 5.12 Overview of international guidelines for corrosion management Notification Name
Date of Country issue
ACI 222R-01
Protection of Metals in Concrete Against Corrosion
2001
USA
BRE-Digest 444
Corrosion of Steel in Concrete Part 3: Protection and Remediation
2000
UK
CS TR 36
Cathodic Protection of Reinforced Concrete
1989
USA
CS TR 37
Model Specification for Cathodic Protection of Reinforced Concrete
1991
USA
CPA Monograph No. 2
An Introduction to Electrochemical Rehabilitation Techniques
1998
UK
CPA Monograph No. 4
Monitoring and Maintenance of Conductive Coating Anode Cathodic Protection Systems
1999
UK
CPA Monograph No. 6
The Principles and Practice of Galvanic 2000 Cathodic Protection for Reinforced Concrete Structures
UK
RILEM Technical Recommendation 124-SRC
“Strategies for repair of concrete structures damaged by steel corrosion”
RILEM
1994
Table 5.13 Overview of international guidelines for maintenance Notification Name
Date of Country issue
ACI 362.2R-00
Guide for Structural Maintenance of Parking Structures
2000
USA
CPA Monograph No. 4
Monitoring and Maintenance of Conductive Coating Anode Cathodic Protection Systems
1999
UK
to detect defects at an early stage avoiding cost and time-extensive repair work. A short overview of existing regulations for maintenance of reinforced concrete structures is given in Table 5.13.
5.3.10 Outlook Subcommittee SC 7 ‘Maintenance and repair of concrete structures’ of Technical committee TC 71 ‘Concrete, reinforced concrete and pre-stressed concrete’ of the ISO (International Organization for Standardization) is currently working on an international standard regarding the protection
Standards and guidelines for repairing concrete structures
159
and repair of concrete structures. This standard will cover the whole area of general principles, condition assessment and design of repair as well as the execution of the repair. The publication of this standard is planned for the end of 2010.
5.4
References
EN 1504-1 2005-7. Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity – Part 1: Definitions, British Standards Institution, London UK. EN 1504-2 2004-10. Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity Part 2: Surface protection systems for concrete, British Standards Institution, London UK. DIN EN 1504-3 2005-12 Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity Part 3: Structural and non-structural repair, Deutsches Institut für Normung, Berlin, Germany. EN 1504-4 2004-11. Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity – Part 4: Structural bonding, British Standards Institution, London UK. EN 1504-5 2004-12. Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity – Part 5: Concrete injection, British Standards Institution, London UK. EN 1504-6 2006-08. Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity – Part 6: Anchoring of reinforcing steel bar, British Standards Institution, London UK. EN 1504-7 2006-06. Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity – Part 7: Reinforcement corrosion protection, British Standards Institution, London UK. EN 1504-8 2004-11. Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity – Part 8: Quality control and evaluation of conformity, British Standards Institution, London UK. prEN 1504-9 2007-12. Products and systems for the protection and repair of concrete structures – Definitions, requirements, quality control and evaluation of conformity – Part 9: General principles for the use of products and systems, British Standards Institution, London UK. EN 1504-10 2003-12. Products and systems for the protection and repair of concrete structures – Definitions, Requirements, Quality control and evaluation of conformity – Part 10: Site application of products and systems and quality control of the works, British Standards Institution, London UK. RILEM TC 124-SRC: Draft recommendation for repair strategies for concrete structures damaged by reinforcement corrosion. RILEM Technical Committees 1994, Ritel Publications Sarl, Bagneux, France.
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5.5
Failure, distress and repair of concrete structures
Appendix
Table A1 International standards for condition evaluation Notification Name
Date of Country issue
ASTM A 370
Standard Test Methods and Definitions for Mechanical Testing of Steel Products
2007
USA
ASTM A 751
Standard Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products
2007
USA
ASTM C 39
Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens
2005
USA
ASTM C 42
Standard Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of Concrete
2004
USA
ASTM C 295
Standard Guide for Petrographic Examination of Aggregates for Concrete
2003
USA
ASTM C 341
Standard Practice for Length Change of Cast, Drilled, or Sawed Specimens of Hydraulic-Cement Mortar and Concrete
2006
USA
ASTM C 457
Standard Test Method for Microscopical Determination of Parameters of the Air-Void System in Hardened Concrete
2008
USA
ASTM C 469
Standard Test Method for Static Modulus of Elasticity and Poisson’s Ratio of Concrete in Compression
2002
USA
ASTM C 496
Standard Test Method for Splitting Tensile Strength of Cylindrical Concrete Specimens
2004
USA
ASTM C 597
Standard Test Method for Pulse Velocity Through Concrete
2002
USA
ASTM C 642
Standard Test Method for Density, Absorption, and Voids in Hardened Concrete
2006
USA
ASTM C 666
Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing
2003
USA
ASTM C 672
Standard Test Method for Scaling Resistance of Concrete Surfaces Exposed to Deicing Chemicals
2003
USA
ASTM C 803
Standard Test Method for Penetration Resistance of Hardened Concrete
2003
USA
ASTM C 805
Standard Test Method for Rebound Number of Hardened Concrete
2002
USA
Standards and guidelines for repairing concrete structures
161
Table A1 Cont’d Notification Name
Date of Country issue
ASTM C 806
Standard Test Method for Restrained Expansion of Expansive Cement Mortar
2004
USA
ASTM C 823
Standard Practice for Examination and Sampling of Hardened Concrete in Constructions
2007
USA
ASTM C 845
Standard Specification for Expansive Hydraulic Cement
2004
USA
ASTM C 856
Standard Practice for Petrographic Examination of Hardened Concrete
2004
USA
ASTM C 876
Standard Test Method for Half-Cell Potentials of Uncoated Reinforcing Steel in Concrete
1999
USA
ASTM C 900
Standard Test Method for Pullout Strength of Hardened Concrete
2006
USA
ASTM C 1040
Standard Test Methods for In-Place Density of Unhardened and Hardened Concrete, Including Roller Compacted Concrete, By Nuclear Methods
2005
USA
ASTM C 1152
Standard Test Method for Acid-Soluble Chloride in Mortar and Concrete
2004
USA
ASTM C 1202
Standard Test Method for Electrical Indication of Concrete’s Ability to Resist Chloride Ion Penetration
2007
USA
ASTM C 1218
Standard Test Method for Water-Soluble Chloride in Mortar and Concrete
2008
USA
ASTM C 1383
Standard Test Method for Measuring the P-Wave Speed and the Thickness of Concrete Plates Using the Impact-Echo Method
2004
USA
ASTM D 4258
Standard Practice for Surface Cleaning Concrete for Coating
2005
USA
ASTM D 4262
Standard Test Method for pH of Chemically Cleaned or Etched Concrete Surfaces
2005
USA
ASTM D 4263
Standard Test Method for Indicating Moisture in Concrete by the Plastic Sheet Method
2005
USA
ASTM D 4541
Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers
2002
USA
ASTM D 4580
Standard Practice for Measuring Delaminations in Concrete Bridge Decks by Sounding
2007
USA
162
Failure, distress and repair of concrete structures
Table A1 Cont’d Notification Name
Date of issue
Country
ASTM D 4748
Standard Test Method for Determining the Thickness of Bound Pavement Layers Using Short-Pulse Radar
2006
USA
ASTM D 4788
Standard Test Method for Detecting Delaminations in Bridge Decks Using Infrared Thermography
2007
USA
ASTM E 84
Standard Test Method for Surface Burning Characteristics of Building Materials
2008
USA
ASTM E 105
Standard Practice for Probability Sampling Of Materials
2004
USA
ASTM E 122
Standard Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot or Process
2007
USA
ASTM G 57
Standard Test Method for Field Measurement of Soil Resistivity Using the Wenner Four-Electrode Method
2006
USA
Table A2 International standards for concrete restoration Notification Name
Date of Country issue
ASTM C 1116
Standard Specification for Fibre-Reinforced Concrete
2008
USA
ASTM C 1140
Standard Practice for Preparing 2003 and Testing Specimens from
USA
Shotcrete Test Panels
ASTM C 1141
Standard Specification for
Admixtures for Shotcrete
2006
USA
Products and systems for the protection and repair of concrete structures – structural and non–structural repair according to EN 1504-3 Test methods – Determination EN 12190 of compressive strength of repair mortar
1998
Measurement of bond strength by pull-off
EN 1542
1999
Determination of shrinkage and expansion
EN 12617-4
2002
Determination of resistance to EN 13295 carbonation
2004
Europe
Standards and guidelines for repairing concrete structures
163
Table A2 Cont’d Notification Name
Date of Country issue
Determination of modulus of elasticity in compression
EN 13412
2006
Part 1: Freeze–thaw cycling with de-icing salt immersion
EN 13687-1, 2, 4
2002
EN 13036-4
2003
Part 2: Thunder–shower cycling (thermal shock) Part 4: Determination of thermal compatibility Method for measurement of slip/skid resistance of a surface: The pendulum test
Determination of the coefficient EN 1770 of thermal expansion
1998
Determination of resistance of EN 13057 capillary absorption
2002
Measurement of chloride ion ingress
EN 13396
2004
Determination of creep in compression for repair products
EN 13584
2003
Resistance to severe chemical EN 13529 attack
2003
Table A3 International standards for strengthening Notification Name
Date of Country issue
ASTM C 881
Standard Specification for Epoxy-Resin-Base Bonding Systems for Concrete
2002
USA
ASTM C 1059
Standard Specification for Latex Agents for Bonding Fresh To Hardened Concrete
1999
USA
ASTM D 3165
Standard Test Method for Strength Properties of Adhesives in Shear by Tension Loading of SingleLap-Joint Laminated Assemblies
2007
USA
ASTM D 3528
Standard Test Method for Strength Properties of Double Lap Shear Adhesive Joints by Tension Loading
2002
USA
164
Failure, distress and repair of concrete structures
Table A3 Cont’d Notification Name
Date of Country issue
Structural bonding according to DIN EN 1504-4 Determination of compressive strength of repair mortar
EN 12190
1998
Determination of flexural properties
EN ISO 178
2003
Determination of adhesion steel-to-steel for characterisation of structural bonding agents
EN 12188
1999
Determination of open time
EN 12189
1999
Determination of modulus of EN 13412 elasticity in compression
2006
Determination of glass EN 12614 transition temperatures of polymers
2004
Determination of the EN 1770 coefficient of thermal expansion
1998
Determination of linear EN 12617-1 shrinkage for polymers and surface protection systems (SPS)
2003
Determination of early age EN 12617-3 linear shrinkage for structural bonding agent
2002
Adhesion by tensile bond EN 12618-2 strength
2004
Determination of the durability
2002
EN 13733
of structural bonding Determination of slant shear EN 12615 strength
1999
Determination of the adhesion EN 12618-2 of injection products, with or without thermal cycling.
2004
Determination of adhesion EN 12636 concrete to concrete
1999
Determination of slant shear EN 12615 1999 strength Determination of fatigue under dynamic loading . Part 1: During cure Part 2: After hardening
EN 13894-1, 2
2002/03
Europe
Standards and guidelines for repairing concrete structures
165
Table A3 Cont’d Notification Name
Date of Country issue
Anchoring of reinforcing steel bar according to DIN EN 1504-6 Testing of anchoring products by the pull-out method
EN 1881
2006
Determination of glass EN 12614 transition temperatures of polymers
2004
Determination of creep under EN 1544 sustained tensile load for synthetic resin products (PC) for the anchoring of reinforcing bars
2006
Europe
Table A4 International standards for surface protection Notification Name
Date of Country issue
Surface protection systems for concrete according to EN 1504-2 Determination of indentation hardness by EN ISO 868 2003 means of a durometer (Shore hardness) Determination of compressive strength of EN 12190 repair mortar
1998
Determination of linear shrinkage for polymers and surface protection systems (SPS)
2003
EN 12617-1
Determination of the coefficient of thermal DIN EN 1770 expansion
1998
Taber abrader
EN ISO 5470-1
1999
Cross-cut test
EN ISO 2409
2007
Determination of carbon dioxide permeability
EN 1062-6
2002
Part 1: Determination of water-vapour transmission rate
EN ISO 7783-1, 2
1999
Part 2: Determination and classification of water-vapour transmission rate Determination of liquid water permeability EN 1062-3
2008
Freeze–thaw cycling with de-icing salt EN 13687-1 immersion
2002
Thunder-shower cycling
EN 13687-2
2002
Thermal cycling without de-icing salt impact
EN 13687-3
2002
Methods of conditioning before testing
EN 1062-11
2002
Europe
166
Failure, distress and repair of concrete structures
Table A4 Cont’d Notification Name
Date of Country issue
Resistance to temperature shock
EN 13687-5
2002
Immersion in liquids other than water
EN ISO 2812-1
2007
Resistance to severe chemical attack
EN 13529
2003
Determination of crack bridging properties EN 1062-7
2004
Fallingweight test, large area indenter
EN ISO 6272-1
2004
Measurement of bond strength by pull-off
EN 1542
1999
Classification using data from reaction to EN 13501-1 fire tests Determination of loss of mass of EN 13581 hydrophobic impregnated concrete after freeze–thaw salt test
2007
Method for measurement of slip/skid EN 13036-4 resistance of a surface: The pendulum test
2003
Drying test for hydrophobic impregnation
EN 13579
2002
Surface protection systems for concrete
EN 1504-2
2004
Methods of conditioning before testing
EN 1062-11
2002
Determination of the electrical resistance
EN 1081
1998
Compatibility on wet concrete;
EN 13578
2003
Water absorption and resistance to alkali EN 13580 for hydrophobic impregnations
2002
Evaluation of degradation of coatings
EN ISO 4628
2003
Determination of film thickness
EN ISO 2808
2007
Table A5 International standards for crack injection Notification Name Concrete injection according to EN 1504-5 Plastics – Urea Formaldehyde and urea/melamine-formaldehyde powder mouldering compounds
EN ISO 527-1, DIN EN ISO 527-2
Date of Country issue 2000
Determination of compressive strength of EN 12190 repair mortar
1998
Determination of the adhesion of injection EN 12618-2 products, with or without thermal recycling – Adhesion by tensile bond strength
2004
Determination of the adhesion of injection EN 12618-3 products, with or without thermal recycling – Slant shear method
2004
Europe
Standards and guidelines for repairing concrete structures
167
Table A5 Cont’d Notification Name
Date of Country issue
Adhesion and elongation capacity of injection products with limited ductility
EN 12618-1
2003
Shrinkage of crack injection products based on polymer binder: volumetric shrinkage
EN 12617-2
2004
Determination of glass transition temperatures of polymers
EN 12614
2004
Determination of tensile strength development for polymers
EN 1543
1998
Determination of water tightness of injected cracks without movement in concrete
EN 14068
2003
Compatibility with concrete
EN 12637-1
2004
Effect of injection products on elastomers
EN 12637-3
2003
Volume and weight changes of injection products after air drying and water storage cycles
EN 14498
2004
Determination of temperature and enthalpy of melting and crystallisation
ISO 11357-3
1999
Determination of thermal compatibility – Thermal cycling without de-icing salt impact
EN 13687-3
2002
Determination of thermal compatibility – Resistance to temperature shock
EN 13687-5
2002
Table A6 International standards for corrosion protection Notification Name
Date of issue
Country
ASTM A 706
Standard Specification for Low-Alloy Steel Deformed and Plain Bars for Concrete Reinforcement
2006
USA
ASTM A 775
Standard Specification for Epoxy-Coated Steel Reinforcing Bars
2007
USA
ASTM G 57
Standard Test Method for Field Measurement of Soil Resistivity Using the Wenner Four-Electrode Method
2006
USA
EN 12696
Cathodic Protection of Steel in Concrete
2000
Europe
168
Failure, distress and repair of concrete structures
Table A6 Cont’d Notification Name Reinforcement corrosion protection according to EN 1504-7 Determination of EN ISO 868 indentation hardness by means of a durometer (Shore hardness)
Date of issue
Country
2003
Europe
Corrosion protection test
EN 15183
2006
Determination of glass transition temperatures of polymers
EN 12614
2004
Shear adhesion of coated steel to concrete (pull-out test)
EN 15184
2006